Both singers rose to fame in the pop world around the same time

Jessica Simpson; Britney Spears. PHOTO: DAVID LIVINGSTON/GETTY; STEVE GRANITZ/WIREIMAGE

Jessica Simpson is laughing off an awkward encounter with a fan.

On Saturday, the singer and fashion mogul, 43, shared on Instagram that she had just been approached by an autograph seeker during an outing to the mall — only, as it turned out, it was a case of mistaken identity.

“The face when someone in the parking lot at the mall asks you for your autograph, but expects you to sign it Britney Spears,” Simpson quipped, alongside a photo of her and daughter Maxwell Drew, 11, making exaggerated shocked faces for the camera.

It’s not all that surprising that a fan might get the two pop stars mixed up. They both rose to fame on the music scene around the same time in the late 1990s and early 2000s, and share a few other notable things in common, including their bright blonde hair, dark brown eyes, Southern roots and childhood stints on the Mickey Mouse Club.

They also both starred in reality shows with their former significant others — Simpson in MTV’s Newlyweds with ex-husband Nick Lachey, and Spears, 41, in UPN’s Britney and Kevin: Chaotic with ex Kevin Federline.

Spears even made her own nod to the duo’s resemblance in a December 2022 Instagram post. “Why do I look EXACTLY like Jessica Simpson ??? Also my face looks so pale 🤧🤧🤧🤔🤔🤔!!!” she wrote alongside a throwback photo of herself sucking in her cheeks, making her look more like the “I Wanna Love You Forever” singer.

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Though the pair was often pitted against each other and portrayed by the media as rivals during their pop heyday, Simpson has openly supported Spears in recent years.

Following the release of the paperback edition of her memoir Open Book in March 2021, Simpson told PEOPLE she admires and empathizes with the “Criminal” singer, especially as they had a similar “coming of age” story.

“I honestly choose not to watch the documentary,” she said, referring to the 2021 unauthorized documentary Framing Britney Spears.

“I didn’t want to watch and bring back any of the dark pieces of my personal coming of age in the music business. I have worked through a lot and want to keep moving forward in my own story on my own path.”

“I admire her ambition, strength and the capability to live unapologetically and authentically,” she added of Spears.

Britney Spears. GETTY IMAGES

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More than two years after Framing Britney Spears was released, Spears is finally ready to open up on her own terms. On Oct. 24, her much-anticipated memoir The Woman in Me will debut.

According to a release, the book promises to reveal the “Toxic” singer’s “incredible journey” while illuminating “the enduring power of music and love — and the importance of a woman telling her own story, on her own terms.”

 Britney Spears Sets Fall Date for ‘Brave’ Memoir ‘The Woman in Me’ — See the Book Cover Reveal (Exclusive)

PEOPLE recently confirmed that five-time Oscar-nominated actress Michelle Williams will narrate the audio edition of the book, with Spears recording a short introduction.

“This book has been a labor of love and all the emotions that come with it,” Spears said in a statement shared with PEOPLE. “Reliving everything has been exciting, heart-wrenching, and emotional, to say the least. For those reasons, I will only be reading a small part of my audiobook.”

“I am so grateful to the amazing Michelle Williams for reading the rest of it,” she added.